Why am I getting an AttributeError when trying to print out
I am learning about urllib2 by following this tutorial http://docs.python.org/howto/urllib2.html#urlerror Running the code below yields a different outcome from the tutorial
import urllib2
req = urllib2.Request('http://www.pretend-o-server.org')
try:
urllib2.urlopen(req)
except urllib2.URLError, e:
print e.reason
Python interpreter spits this back
Traceback (most recent call last):
File "urlerror.py", line 8, in <module>
print e.reason
AttributeError: 'HTTPError' object has no attribute 'reason'
How come this is happening?
UPDATE
When I try to print out the code attribute it works fine
import urlli开发者_C百科b2
req = urllib2.Request('http://www.pretend-o-server.org')
try:
urllib2.urlopen(req)
except urllib2.URLError, e:
print e.code
Depending on the error type, the object e
may or may not carry that attribute.
In the link you provided there is a more complete example:
Number 2
from urllib2 import Request, urlopen, URLError
req = Request(someurl)
try:
response = urlopen(req)
except URLError, e:
if hasattr(e, 'reason'): # <--
print 'We failed to reach a server.'
print 'Reason: ', e.reason
elif hasattr(e, 'code'): # <--
print 'The server couldn\'t fulfill the request.'
print 'Error code: ', e.code
else:
# everything is fine
Because there is no such attribute. Try:
print str(e)
and you will get nice:
HTTP Error 404: Not Found
The reason I got the AttributeError was because I was using OpenDNS. Apparently even when you pass in a bogus URL, OpenDNS treats it like it exists. So after switching to Googles DNS server, I am getting the expected result which is:
[Errno -2] Name or service not known
Also I should mention the traceback I got for running this code which is everything excluding try and except
from urllib2 import Request, urlopen, URLError, HTTPError
req = Request('http://www.pretend_server.com')
urlopen(req)
is this
Traceback (most recent call last):
File "urlerror.py", line 5, in <module>
urlopen(req)
File "/usr/lib/python2.6/urllib2.py", line 126, in urlopen
return _opener.open(url, data, timeout)
File "/usr/lib/python2.6/urllib2.py", line 397, in open
response = meth(req, response)
File "/usr/lib/python2.6/urllib2.py", line 510, in http_response
'http', request, response, code, msg, hdrs)
File "/usr/lib/python2.6/urllib2.py", line 435, in error
return self._call_chain(*args)
File "/usr/lib/python2.6/urllib2.py", line 369, in _call_chain
result = func(*args)
File "/usr/lib/python2.6/urllib2.py", line 518, in http_error_default
raise HTTPError(req.get_full_url(), code, msg, hdrs, fp)
urllib2.HTTPError: HTTP Error 404: Not Found
which a kind gentle(wo)man? from IRC #python told me was highly strange and then asked if I was using OpenDNS to which I replied yes. So they suggested I switch it to Google's which I proceeded to do.
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